Method of saturating double width felt



Nov. l0, 1931. F. B. MANKER 1,831,630

METHOD OF SATURATING DOUBLE WIDTH FELT Filed Jan. 5, 1929 d@ fl.

Patented Nv.1o, 1931 UNrr-D. STATESI PATENT OFFICE PENNSYLVANIA,msxsrefNn. 'ro 'rma Y., A CORPORATION 0F NEW JERSEY METHOD 0F SATUMTI'NGDOUBLE WDTH.' FELT Application led .Tanuary 5,

My invention pertains to the saturation of felt with tar, asphalt, orlike materials for the production of building paper, artificial ,tionrelates more particularly to shingles, and similar products. My invenanimprovement in the saturation process wherebyv a uniform degree ofsaturation is attained throughoutthewidth of the felt blanket.

.In the usual process a roll of felt is slowly unwound by machinery. Thefelt passes over drier drums where some of its moisture is removed andis then immersed in or otherwise saturated with the hot impregnatingfluid. The saturated felt then passes through squeeze rolls or othermechanisms adapted to impart any desired surface appearance andsubsequently the felt is allowed to cool so that the saturant mayharden.

Considerable difficulty has been experi enced in the past in securing auniform saturation of the felt, the greatest diiiiculty occur? ring inthe case of the wider blankets. It was found that a layerof excesssaturant apeared o'n the surface ofthe blanket, particuarly in thecenter section. This surface saturant was found to cause excessive scrapand to increase manufacturing hazards. I have now discovered that bysteaming the felt, prior to submitting it tothe saturating process, aneven degree of saturation may be obtained throughout the width of thefelt and the presence of surface saturant may be eliminated.

The fact that the presence of moisture .in the felt tends to retard itssaturation is well known and it is for this reason that it is customarytotdry the felt blanket to some extent before impregnation. As theresult of my experiments I am of the opinion that the difficultyexperienced in securing a uniform saturation of the entire width of thefelt blanket hasbeen due to the varying moisture content of the felt.This material is ordinarily stored in rolls, and the edges of these(rolls appear. to absorb more moisture than the center portion. Passingthe blanket over drier drums prior to impregnation removes some moisturefrom vthe felt but does not e ualize the moisture content across thewidth ofthe blanket. As a consequence,

1929. i serial No. amuse. l

of the felt entering the impregnating bath icontain more moisture thanthe center porion, enough toresult in a saturation of the edges 1t willalso cause an over-saturation of the center portion.l

I have now discovered that I may obtain a uniform saturation of thefelt, regardless of the blanket width, by producing a uniform moisturecontent therein prior to saturation. I may accomplish this result byexposing the felt to steam jets so that the total moisture present inthe felt is increased, since under these circumstances the variance inthe origi. nal moisture content across the width of the felt becomesinconsequential and all sections and if the impregnation iscomplete ofthe felt offer about the same resistance' to saturation. However, Iprefer to vary this procedure, somewhat,"sincethe presence of a largeamount of moisture saturation more difficult.

in the felt makes For the reasons indicated I prefer to' dry the felt tosome extent -prior tothe steaming treatment so that the amount ofmoisturere 'quired to be added to. produce a substantial uniformitythroughout the widthy of the blanket is reduced. I also prefer to drythe blanket somewhat, after the steam treatment, y

so that .it will not offer unusual resistance to saturation. v

In the appended drawings I have indicated the operation of my ferredform. InV the drawings, Fig. 1 shows a cross-sectional sketch of asuitable apparatus for the ractise of my-invention and Fig. 2 shows aace view of the drier drum over which 'the felt passes during thesteaming process. Like letters of reference are used in the two gures.

In Fig. 1, (A) is a roll of .felt adapted to be unwound in the process.The felt (A) passes over drier drum (B) where its moisture content issomewhat reduced. The felt then travels around drier drum (C) whereit-is subjected to a steaming process by means of steam jets (G, G) onsteam ipe (H), after which its passes over drier (li'um (D i, where itsmoisture content is again reduced.

The felt then passes over idler- (I) andenters. the edges saturator (E)which is 'shown diagrammatfy rocess in its pre@ ically. The saturatedfelt rising from the saturator passes over idler (F) after which it maycontinue on through squeeze rolls, cooling frames, and the like, whichare not shown in the drawings. 2

Fig. 2 represents a face view of the drier drum (C) carrying the felt(A) which is being treated with steam by means of jets (G, G) on steampipe (H).

In practise I ,prefer to apply the steam at a pressure of about tenpounds or less by means of jets spaced about three inches apart on asteam pipe held in a plane parallel to the surface of the felt, thesteam jets themselves being located about three inches from the felt. Ihave also found it advisable to place a drain on the steam linesupplying the jets so that free water may be removed .from-the stem. C

It should be understood that the preferred embodiment of my invention,thus described, is illustrative but not limiting. For example the dryingof the felt prior to and subsequent to the steaming treatment may beeliminated without` departing from the spirit of the invention. On theother hand, drier drums'in addition to those shown in the drawings maybe used, or in place of the steam heated revolving drums some otherdrying means may be employed. Also the steam treatment may be confinedto the central portion of the fabric so that the moisture content'ofthis portion is substantially equal to that of the ends of the fabric.While I prefer tov impart the required moisture to the felt by thesteaming treatmentdescribed I may, alternatively, add this moisture inthe form of a water spray or in any other convenient manner.

Now having described my invention, I claim: l

1. A process for the production of an impregnated felt which comprisesheating said .felt to remove a portion of the naturally containedmoisture` adding moisture 4to said felt so that the total moisturecontent thereof is substantially uniform across its width, andsubmitting said felt to the action of a saturant.

2. A process for the production of an impregnated felt which comprisesheating said felt to remove a portion of the naturally containedmoisture; adding moisture to said felt so that the total moisturecontent thereof is substantially uniform across its width, partiallydrying said felt, and submitting said felt to the action of asaturant.

' In testimony whereof, I have hereunto af.

Xed my signature. K l f FRANK BRADFORDMANKER..

